From d70dbe431a1d95afb8d18de34ca2f8597f9151a3 Mon Sep 17 00:00:00 2001
From: micdoodle8 <mitchpetrie29@gmail.com>
Date: Thu, 12 Sep 2013 17:28:32 -0400
Subject: [PATCH] Fix concurrent modification exception when unloading chunks.

---
 .../api/transmitters/TransmitterNetworkRegistry.java         | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/common/mekanism/api/transmitters/TransmitterNetworkRegistry.java b/common/mekanism/api/transmitters/TransmitterNetworkRegistry.java
index a1654a09e..cad3ec13f 100644
--- a/common/mekanism/api/transmitters/TransmitterNetworkRegistry.java
+++ b/common/mekanism/api/transmitters/TransmitterNetworkRegistry.java
@@ -3,7 +3,6 @@ package mekanism.api.transmitters;
 import java.util.EnumSet;
 import java.util.HashSet;
 import java.util.Set;
-
 import net.minecraft.tileentity.TileEntity;
 import net.minecraft.world.chunk.Chunk;
 import net.minecraft.world.chunk.IChunkProvider;
@@ -57,7 +56,9 @@ public class TransmitterNetworkRegistry implements ITickHandler
 	
 	public void pruneEmptyNetworks()
 	{
-		for(ITransmitterNetwork e : networks)
+	    HashSet<ITransmitterNetwork> copySet = new HashSet<ITransmitterNetwork>(networks);
+	    
+		for(ITransmitterNetwork e : copySet)
 		{
 			if(e.getSize() == 0)
 			{